Major improvement in OSM charms

- Adapt all new operator charms to use the same pattern. They are all
using now this library that encapsulates the common logic for all
charms: https://github.com/davigar15/ops-lib-charmed-osm. That will be
eventually moved to gitlab, when it has a PyPI repository available
- Add unit tests to all charms
- Modify installer and bundles to point to the new charms
- Improve the build.sh script for building the charms

Change-Id: I0896ceb082d1b6a76b3560c07482a4135a220a3f
Signed-off-by: David Garcia <david.garcia@canonical.com>
diff --git a/installers/charm/ro/src/pod_spec.py b/installers/charm/ro/src/pod_spec.py
index 6c91baf..1beba17 100644
--- a/installers/charm/ro/src/pod_spec.py
+++ b/installers/charm/ro/src/pod_spec.py
@@ -45,8 +45,9 @@
         )
         if values.get("enable_ng_ro", True)
         else True,
-        "log_level": lambda value, _: isinstance(value, str)
-        and value in ("INFO", "DEBUG"),
+        "log_level": lambda value, _: (
+            isinstance(value, str) and value in ("INFO", "DEBUG")
+        ),
         "vim_database": lambda value, values: (
             isinstance(value, str) and len(value) > 0
         )